Add pressAndHoldInterval to MouseArea

Introduce pressAndHoldInterval to allow setting the pressAndHold delay
per-MouseArea.

[ChangeLog][QtQml][MouseArea] Introduce pressAndHoldInterval property,
which controls the elapsed time before pressAndHold is emitted.

Task-Id: QTBUG-47662
Change-Id: Ic2173335033a6ed0d4b652333020f030de63a8e7
Reviewed-by: Michael Brasser <michael.brasser@live.com>

src/quick/items/qquickitemsmodule.cpp

@@ -368,6 +368,8 @@ static void qt_quickitems_defineModule(const char *uri, int major, int minor)
 #if QT_CONFIG(quick_shadereffect)
     qmlRegisterType<QQuickBorderImageMesh>("QtQuick", 2, 8, "BorderImageMesh");
 #endif
+
+    qmlRegisterType<QQuickMouseArea, 9>(uri, 2, 9, "MouseArea");
 }
 
 static void initResources()

src/quick/items/qquickmousearea.cpp

@@ -60,7 +60,8 @@ Q_DECLARE_LOGGING_CATEGORY(DBG_HOVER_TRACE)
 QQuickMouseAreaPrivate::QQuickMouseAreaPrivate()
 : enabled(true), scrollGestureEnabled(true), hovered(false), longPress(false),
   moved(false), stealMouse(false), doubleClick(false), preventStealing(false),
-  propagateComposedEvents(false), overThreshold(false), pressed(0)
+  propagateComposedEvents(false), overThreshold(false), pressed(0),
+  pressAndHoldInterval(-1)
 #if QT_CONFIG(draganddrop)
   , drag(0)
 #endif
@@ -685,7 +686,7 @@ void QQuickMouseArea::mousePressEvent(QMouseEvent *event)
 #endif
         setHovered(true);
         d->startScene = event->windowPos();
-        d->pressAndHoldTimer.start(QGuiApplication::styleHints()->mousePressAndHoldInterval(), this);
+        d->pressAndHoldTimer.start(pressAndHoldInterval(), this);
         setKeepMouseGrab(d->stealMouse);
         event->setAccepted(setPressed(event->button(), true, event->source()));
     }
@@ -1294,6 +1295,48 @@ void QQuickMouseArea::setCursorShape(Qt::CursorShape shape)
 
 #endif
 
+
+/*!
+    \qmlproperty int QtQuick::MouseArea::pressAndHoldInterval
+    \since 5.9
+
+    This property overrides the elapsed time in milliseconds before
+    \c pressAndHold is emitted.
+
+    If not explicitly set -- or after reset -- the value follows
+    \c QStyleHints::mousePressAndHoldInterval.
+
+    Typically it's sufficient to set this property globally using the
+    application style hint. This property should be used when varying intervals
+    are needed for certain MouseAreas.
+
+    \sa pressAndHold
+*/
+int QQuickMouseArea::pressAndHoldInterval() const
+{
+    Q_D(const QQuickMouseArea);
+    return d->pressAndHoldInterval > -1 ?
+        d->pressAndHoldInterval : QGuiApplication::styleHints()->mousePressAndHoldInterval();
+}
+
+void QQuickMouseArea::setPressAndHoldInterval(int interval)
+{
+    Q_D(QQuickMouseArea);
+    if (interval != d->pressAndHoldInterval) {
+        d->pressAndHoldInterval = interval;
+        emit pressAndHoldIntervalChanged();
+    }
+}
+
+void QQuickMouseArea::resetPressAndHoldInterval()
+{
+    Q_D(QQuickMouseArea);
+    if (d->pressAndHoldInterval > -1) {
+        d->pressAndHoldInterval = -1;
+        emit pressAndHoldIntervalChanged();
+    }
+}
+
 /*!
     \qmlpropertygroup QtQuick::MouseArea::drag
     \qmlproperty Item QtQuick::MouseArea::drag.target

src/quick/items/qquickmousearea_p.h

@@ -84,6 +84,7 @@ class Q_QUICK_PRIVATE_EXPORT QQuickMouseArea : public QQuickItem
     Q_PROPERTY(Qt::CursorShape cursorShape READ cursorShape WRITE setCursorShape RESET unsetCursor NOTIFY cursorShapeChanged)
 #endif
     Q_PROPERTY(bool containsPress READ containsPress NOTIFY containsPressChanged REVISION 1)
+    Q_PROPERTY(int pressAndHoldInterval READ pressAndHoldInterval WRITE setPressAndHoldInterval NOTIFY pressAndHoldIntervalChanged RESET resetPressAndHoldInterval REVISION 9)
 
 public:
     QQuickMouseArea(QQuickItem *parent=0);
@@ -125,6 +126,10 @@ public:
     void setCursorShape(Qt::CursorShape shape);
 #endif
 
+    int pressAndHoldInterval() const;
+    void setPressAndHoldInterval(int interval);
+    void resetPressAndHoldInterval();
+
 Q_SIGNALS:
     void hoveredChanged();
     void pressedChanged();
@@ -152,6 +157,7 @@ Q_SIGNALS:
     void exited();
     void canceled();
     Q_REVISION(1) void containsPressChanged();
+    Q_REVISION(9) void pressAndHoldIntervalChanged();
 
 protected:
     void setHovered(bool);

src/quick/items/qquickmousearea_p_p.h

@@ -95,6 +95,7 @@ public:
     bool propagateComposedEvents : 1;
     bool overThreshold : 1;
     Qt::MouseButtons pressed;
+    int pressAndHoldInterval;
 #if QT_CONFIG(draganddrop)
     QQuickDrag *drag;
 #endif

tests/auto/quick/qquickmousearea/data/pressAndHold.qml

@@ -0,0 +1,12 @@
+import QtQuick 2.9
+
+Item {
+    width: 100
+    height: 100
+
+    MouseArea {
+        id: mouseArea
+        objectName: "mouseArea"
+        anchors.fill: parent
+    }
+}

tests/auto/quick/qquickmousearea/tst_qquickmousearea.cpp

@@ -127,6 +127,8 @@ private slots:
     void containsPress();
     void ignoreBySource();
     void notPressedAfterStolenGrab();
+    void pressAndHold_data();
+    void pressAndHold();
 
 private:
     int startDragDistance() const {
@@ -2098,6 +2100,49 @@ void tst_QQuickMouseArea::notPressedAfterStolenGrab()
     QVERIFY(!ma->pressed());
 }
 
+void tst_QQuickMouseArea::pressAndHold_data()
+{
+    QTest::addColumn<int>("pressAndHoldInterval");
+    QTest::addColumn<int>("waitTime");
+
+    QTest::newRow("default") << -1 << QGuiApplication::styleHints()->mousePressAndHoldInterval();
+    QTest::newRow("short") << 500 << 500;
+    QTest::newRow("long") << 1000 << 1000;
+}
+
+void tst_QQuickMouseArea::pressAndHold()
+{
+    QFETCH(int, pressAndHoldInterval);
+    QFETCH(int, waitTime);
+
+    QQuickView window;
+    QByteArray errorMessage;
+    QVERIFY2(initView(window, testFileUrl("pressAndHold.qml"), true, &errorMessage), errorMessage.constData());
+    window.show();
+    window.requestActivate();
+    QVERIFY(QTest::qWaitForWindowExposed(&window));
+    QQuickItem *root = window.rootObject();
+    QVERIFY(root != 0);
+
+    QQuickMouseArea *mouseArea = window.rootObject()->findChild<QQuickMouseArea*>("mouseArea");
+    QVERIFY(mouseArea != 0);
+
+    QSignalSpy pressAndHoldSpy(mouseArea, &QQuickMouseArea::pressAndHold);
+
+    if (pressAndHoldInterval > -1)
+        mouseArea->setPressAndHoldInterval(pressAndHoldInterval);
+    else
+        mouseArea->resetPressAndHoldInterval();
+
+    QElapsedTimer t;
+    t.start();
+    QTest::mousePress(&window, Qt::LeftButton, Qt::NoModifier, QPoint(50, 50));
+    QVERIFY(pressAndHoldSpy.wait());
+    // should be off by no more than 20% of waitTime
+    QVERIFY(qAbs(t.elapsed() - waitTime) < (waitTime * 0.2));
+    QTest::mouseRelease(&window, Qt::LeftButton, Qt::NoModifier, QPoint(50, 50));
+}
+
 QTEST_MAIN(tst_QQuickMouseArea)
 
 #include "tst_qquickmousearea.moc"